Newborn screening for congenital hypothyroidism in a public sector hospital

Congenital hypothyroidism if left untreated results in growth failure, irreversible mental retardation, and cretinism. National neonatal screening programs are therefore, launched to diagnose congenital hypothyroidism and manage it timely. To screen newborns for congenital hypothyroidism in two public sector hospitals of Lahore. Cross sectional descriptive study conducted at departments of Gynae/Obs and Pediatric Shaikh Zayed Hospital and Jinnah Hospital, Lahore from February 2010 to November 2011. Awareness brochures for congenital hypothyroidism were developed and attached with the antenatal card of each pregnant case attending antenatal clinic at Gynae/Obs OPD. Newborns who had stayed in hospital for more than 24 hour, and whose parents consented for heal prick were tested for blood spot thyroid-stimulating hormone. Results were reported within four days and thyroid-stimulating hormone >/= 20mIU/L was taken as high value. Parents of those neonates who had high value were contacted to give a fresh sample for confirmation. Confirmed results were provided within next 4-5 days to the parents and treating pediatrician for appropriate treatment. A total of 1357 samples were screened using blood spot thyroid-stimulating hormone and out of these 1330 were normal [< 20mIU/L] while 27 had high levels [>/= 20mIU/L]. These 27 neonates were further tested using confirmatory tests for serum thyroid-stimulating hormone, T3 and T4. After confirmatory tests only one case had congenital hypothyroidism who was referred for treatment. Three cases were suspected to have subclinical hypothyroidism and these were retested after six months which, picked another case of confirmed subclinical hypothyroidism who was referred for treatment. The incidence of congenital hypothyroidism was 2 out of 1357 cases. The screening could pick 2 cases of hypothyroidism from a total of 1357 cases which is high when compared to global rates. Routine screening of neonates for thyroid disease can pick the disease early and thus prevent later complications

Alteraçöes somáticas, hereditárias ou congênitas de funçäo tiróidea associadas a mutaçöes no receptor de TSH / Hereditary or congenital somatic changes of the thyroid function associated to mutation in the TSH receptor

As mutaçoes no receptor de TSH condicionam dois tipos de resposta fenótípica com quadro de hipotireoidismo/eutireoidismo (resistência da célula folicular ao TSH) ou hipertireoidismo (adenoma tóxico, tireotoxicose familiar ou congênita). Na ausência de resposta da célula tireóidea ao TSH nao há elevaçao de AMP cíclico após TSH "in vitro" e verificou-se, a nível molecular, mutaçoes de ponto no gene do receptor de TSH, afetando a cadeia extracelular (posiçoes 583 e 599). Nas três irmas com este defeito, os alelos mutantes foram herdados, respectivamente, da mae (posiçao 583) e do pai (posiçao 599). Anímais com o mesmo tipo de defeito (camundongos hyt/hyt e gatos dfc/dfc) apresentam mutaçao de ponto no IV anel intramembranal (nucleotídeo 1666). Em adenomas tóxicos foram descritas mutaçoes que afetam, com grande freqüência, a VI alça intramembranal do gene do rTSH. Tais mutaçoes podem ser evidenciadas "in vivo" pelo estudo de células tireóideas do nódulo, obtidas por punçao biópsia, onde polimorfismos seriam detectados por enzimas restritivas específicas. Em tireotoxicose nao-autoimune familiar, com transmissao autossômica dominante, também se encontram mutaçoes de ponto em alças intramembranais. Um único caso de hipertireoidismo congênito nao autoimune foi recentemente descrito com substituiçao de prolina por leucina no VI anel intramembranal do receptor de TSH. Conclui-se que mutaçoes no receptor do TSH produzem grande variedade de expressao fenotípica e podem ser responsáveis por outras alteraçoes da fisiopatologia tireóidea.

Neonatal screening for congenital hypothyroidism in Saudi Arabia: the national programme experience

In this report, we review our experience with the national screening programme for congenital hypothyroidism [CH] which was established in 1989. Babies who were born at Ministry of Health hospitals, private and other governmental hospitals were screened at birth for CH. Cord blood TSH + T4 are measured. TSH was assayed on single specimens, using the Delfia immunofluorescent technique [Pharmacia Diagnostic, Wallacory, Finland]. Infants were recalled, for confirmatory tests, if TSH > 60 mU/l or TSH > 30 < 60 with T4 < 80 nmol/l. Thyroid scanning was performed in biochemically confirmed cases. Out of 759,986 neonates screened, 237 were diagnosed to have CH giving an incidence of 1: 3205. Our recall rate was 0.13%. The cost of screening per specimen was SR 12 [3.2 US$]. The mean age of recall was 21 days [range: 6-64]. The majority of infants lacked clinical signs and symptoms of hypothyroidism. Thyroid scans showed the most common aetiology to be thyroid ectopy followed by dyshormonogenesis and aplasia. In conclusion, the incidence of CH was among the highest in the world. Our protocol showed an acceptable recall rate and proved to be cost effective. Mass cord blood screening is practical and feasible and should continue to be an important part of the overall preventive programme in the Kingdom

Anticuerpos antitiroideos en hipotiroidismo congénito / Antithyroid antibodies in congenital hypothyroidism

El papel que los anticuerpos antitiroideos maternos pueden desempeñar en la etiopatogenia del hipotiroidismo congénito por atireosis es discutible. En este estudio se midieron los niveles séricos de antivuerpos antitiroideos en 12 pacientes hipotiroideos y en sus madres, con la finalidad de detectar la posible asociación entre enfermedad tiroidea autoinmune materna y displasia tiroidea fetal. En dos pacientes hubo anticuerpos antitiroglobulina, lo que apoya la teoría de la existencia de un proceso inmunológico contra la tiroides fetal en las primeras ocho semanas de festación, pero no descarta la existencia y/o coexistencia de otros factores etiopatogénicos

Profile of thyroid disorders in a referral centre in north India.

From 1983-88, 157 patients were investigated in our clinic for thyroid disorders: 117 (75%) were hypothyroid, 10 (6%)-hyperthyroid, and 30 had euthyroid goiters. Average age of presentation of congenital hypothyroids was 4.07 years. Children with goitrous hypothyroidism (n = 19) were divided into: (i) thyroiditis: RAIU low and patchy, TMA positive: 2 children; (ii) dyshormonogenesis: RAIU high, family history positive, perchlorate discharge test positive: 2 children; (iii) iodine deficiency: RAIU high, urinary iodine low: 2 children, and (iv) cause unknown: RAIU normal or high, other investigations normal: 13 children. Ninety eight hypothyroid children without goiter were divided into 6 groups: (i) athyreosis: RAIU low, no thyroid tissue identifiable (n = 39); (ii) hypoplasia: RAIU low, gland small, in normal position (n = 7); (iii) ectopia: RAIU low, gland in ectopic position (n = 24); (iv) thyroiditis: TMA positive (n = 2); (v) iodine deficiency: low urinary iodine (n = 1); and (vi) cause unknown: RAIU and scan normal, other investigations normal and not done (n = 8). Proportionate short stature was present in 44.4% children. Twenty two children presented only with growth failure; 72% of them had dysgenetic glands. Early onset marked the group with hyperthyroidism (n = 10). Euthyroid goiter was present in 30 (19%). Hypothyroidism is still being diagnosed very late. All children with growth failure, even if proportionate, must have thyroid status evaluated.